linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	X86 ML <x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
	Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	syzbot+20191dc583eff8602d2d@syzkaller.appspotmail.com
Subject: Re: [PATCH] crypto: add missing kernel_fpu_end() call
Date: Fri, 6 Aug 2021 16:06:11 +0530	[thread overview]
Message-ID: <YQ0Qm+Xs1g/7Eant@fedora> (raw)
In-Reply-To: <CAMj1kXEYymiYaMUobuncmyO-vQxHrOByc7wQn4rKK_wdKuLgXQ@mail.gmail.com>

Hi,

On Fri, Aug 06, 2021 at 11:07:43AM +0200, Ard Biesheuvel wrote:
> On Fri, 6 Aug 2021 at 11:05, Ard Biesheuvel <ardb@kernel.org> wrote:
> >
> > On Fri, 6 Aug 2021 at 10:23, Herbert Xu <herbert@gondor.apana.org.au> wrote:
> > >
> > > On Fri, Jul 30, 2021 at 07:11:55PM +0530, Shreyansh Chouhan wrote:
> > > > xts_crypt() code doesn't call kernel_fpu_end() after calling
> > > > kernel_fpu_begin() if walk.nbytes is 0. Add a call to kernel_fpu_end()
> > > > for this case.
> > > >
> > > > Reported-by: syzbot+20191dc583eff8602d2d@syzkaller.appspotmail.com
> > > > Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
> > > > ---
> > > >  arch/x86/crypto/aesni-intel_glue.c | 3 +++
> > > >  1 file changed, 3 insertions(+)
> > >
> > > Ard?
> > >
> > > > diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
> > > > index 2144e54a6c89..bd55a0cd7bde 100644
> > > > --- a/arch/x86/crypto/aesni-intel_glue.c
> > > > +++ b/arch/x86/crypto/aesni-intel_glue.c
> > > > @@ -894,6 +894,9 @@ static int xts_crypt(struct skcipher_request *req, bool encrypt)
> > > >                       kernel_fpu_begin();
> > > >       }
> > > >
> > > > +     if (walk.nbytes == 0)
> > > > +             kernel_fpu_end();
> > > > +
> >
> > Don't we end up calling kernel_fpu_end() twice this way if we do enter
> > the while() loop at least once?
> >

Oh ha, we do. I missed that.

> 
> How about the below instead, does that work?
> 

This should work. I will resend the updated patch.

> --- a/arch/x86/crypto/aesni-intel_glue.c
> +++ b/arch/x86/crypto/aesni-intel_glue.c
> @@ -849,7 +849,7 @@ static int xts_crypt(struct skcipher_request *req,
> bool encrypt)
>                 return -EINVAL;
> 
>         err = skcipher_walk_virt(&walk, req, false);
> -       if (err)
> +       if (err || !walk.nbytes)
>                 return err;
> 
>         if (unlikely(tail > 0 && walk.nbytes < walk.total)) {

Thanks a lot for the review.

Regards,
Shreyansh Chouhan

  reply	other threads:[~2021-08-06 10:36 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-30 13:41 Shreyansh Chouhan
2021-08-06  8:23 ` Herbert Xu
2021-08-06  9:05   ` Ard Biesheuvel
2021-08-06  9:07     ` Ard Biesheuvel
2021-08-06 10:36       ` Shreyansh Chouhan [this message]
2021-08-09 14:10         ` [PATCH] crypto: xts_crypt() return if walk.nbytes is 0 Shreyansh Chouhan
2021-08-17 14:18           ` Ard Biesheuvel
2021-08-20  8:31           ` Herbert Xu
2021-08-20 11:14             ` Ard Biesheuvel
2021-08-20 12:53               ` Herbert Xu
2021-08-22  3:45                 ` [PATCH v2] " Shreyansh Chouhan
2021-08-27  8:38                   ` Herbert Xu
2021-08-22  3:48                 ` [PATCH] " Shreyansh Chouhan
2021-08-22 13:23                 ` Ard Biesheuvel

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YQ0Qm+Xs1g/7Eant@fedora \
    --to=chouhan.shreyansh630@gmail.com \
    --cc=ardb@kernel.org \
    --cc=bp@alien8.de \
    --cc=davem@davemloft.net \
    --cc=herbert@gondor.apana.org.au \
    --cc=hpa@zytor.com \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=syzbot+20191dc583eff8602d2d@syzkaller.appspotmail.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    --subject='Re: [PATCH] crypto: add missing kernel_fpu_end() call' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).